The first 2 games I made were indexed almost immediately, but the next 3 games that I made and published over the course of six months have still not been indexed; all these games meet the requirements for indexing. Has anyone encountered a similar problem?

Hi!

Yes, same thing here. My game has never been indexed since being published 5 months ago, and has never appeared in any searches because of that. Maybe it has something to do with requirements for indexing, I don't know how strict they are.